What is the rat pop in 1990?
What does the model predict the rat pop was in the year 2005?

Answer:
Pop in 1990 = 81 million rats
Pop in 2005 = 127 million rats
Step-by-step explanation:
Given the function, the population of rats in 1990 is when we replace t with "0" which strictly gives the coefficient 81 that represents 81 million rats.
The rat population in 2005 is given by the formula when t = 15
This is: approximately 127 million rats.